Hi, I'm debugging a timing problem with b43, can you tell me exactly when the timestamp iwl4965 shows in radiotap is taken? Is it the first bit of the preamble? When associated to my b43 AP, I'd expect the difference between the beacon/proberesp timestamp and the MAC timestamp of the iwl4965 monitor mode to be 192us for the MAC header and another 192us for the PLCP preamble/PLCP header, a total of 384 us. However, when I have just associated, the difference starts out at 383us and decreases, down to ~370us and then varies between 370-380us, afaict never reaching 384us. The strange thing is that it doesn't seem to recover. No matter which of the timers is actually wrong (I guess I could find out by comparing with the system timestamp and hoping that the delay through mac80211 into wireshark is constant) shouldn't it recover the time? Another problem is that when I enable powersave on the iwl4965, I see no beacons at all. And oddly, the difference between the timestamp in the probe responses and the iwl4965 MAC timestamp starts varying wildly, up to almost 5000us. I guess that b43 has a timing problem otherwise we'd be seeing totally bad behaviour of iwl4965 on stock APs. I'm just trying to understand the problem better right now. Do you know when iwl4965 will resync the timer? Thanks, johannes
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